ECAT Pre General Science MCQ Test With Answer for Mathematics Chapter 9

Out of 40 consecutive natural numbers, two are chosen at random. Probability that the sum of the numbers is odd, is

• 14 / 29 A
• 20 / 39 B
• 1 / 2 C
• n D

A bag contains 7 whit, 5 black and 4 rd balls. If two balls are drawn at random from the bag, the probability that they are not of the same color is

• 73 / 120 A
• 83 / 120 B
• 67 / 120 C
• 43 / 120 D

The number of ways of arranging the letter AAAAA BBB CCC D EE F in a row when no two C's are together is

• 
  A
• 
  B
• 
  C
• 
  D

• 8 A
• 1/56 B
• 56 C
• None of these D

Form a group of 5 men and 3 women, a committee of 4 persons is to be selected randomly. The probability that there is a majority of men is

• 1/4 A
• 1/3 B
• 1/2 C
• 1/6 D

The domain of an infinite sequence is a

• Set of natural numbers A
• R B
• Subset of N C
• None of the above D

Number of selections of n different things out of n

• 1 A
• nPr B
• n! C
• nPr D

A dice is rolled. The probability that the dots on the top are greater than 4 is

• 1/6 A
• 1/3 B
• 1/2 C
• 1 D

The number of the diagonals of a 6 sided figure is

• 15 A
• 21 B
• 9 C
• 6 D

Eight chairs are numbered 1 to 8. Two women and three men wish to occupy one chair each. First, the women choose the chairs from amongst the chairs marked 1 to 4 and then the men select the chairs from amongst the remaining. The number of possible arrangement is

• ⁶C₃x ⁴C₂ A
• ⁴C₂x ⁴P₃ B
• ⁴P₂x ⁶P₃ C
• None of these D

Four cards are drawn at random from a pack of 52 playing cards. The probability of getting all the four cars of the same suit is

• 44/4165 A
• 22/4165 B
• 11/4165 C
• None of these D

0! = ______

• 0 A
• 1 B
• 2 C
• Not defined D

• 
  A
• 
  B
• 
  C
• 
  D

In school there are 150 students Out of these 80 students enrolled for mathematics class 50 enrolled for English class and 60 enrolled for Physics class The student enrolled for English cannot attend any other class but the students of mathematics and Physics can take two courses at a time Find the number of students who have taken both physics and mathematics.

• 40 A
• 30 B
• 50 C
• 20 D

In a country 55% of the male population has houses in cities while 30% have houses both in cities and in villages find the percentage of the population that has houses only in villages

• 45 A
• 30 B
• 25 C
• 50 D

If n is a positive integer then n! is

• (n - 1) (n - 2) .....3,.2.1 A
• n(n - 1) (n - 2) ...3.2.1 B
• n(n - 1 ) ( n -2) ... 3 C
• None of these D

A machine operates if all of its three components function. The probability that the first component fails during the year is 0.14, the second component fails is 0.10 and the third component fails is 0.05. the probability that the machine will fail during the year is

• 0.2647 A
• 0.2692 B
• 0.3647 C
• None of these D

9. 8. 7. 6= ______

• 
  A
• 
  B
• 
  C
• 
  D

How many signals can be given by 5 flags of different colours, using 3 flags at a time

• 120 A
• 60 B
• 24 C
• 15 D

The number of permutations of n objects of which there are n₁like of one kind, n₂like of the second kind and n₃like objects of third kind are

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  D

How many 3 digit numbers can be formed by using each one of the digit 2, 3, 5, 7, 9 only once?

• 15 A
• 24 B
• 60 C
• 120 D

A bag contains 3 white, 4 black and 2 red balls. If 2 balls are drawn at random, then the probability that both the ball are white is

• 1/18 A
• 1/12 B
• 1/36 C
• None of these D

The value of n, when ⁿP₂= 20 is

• 3 A
• 4 B
• 6 C
• 5 D

n(n - 1) (n - 2) in factorial form is

• 
  A
• 
  B
• 
  C
• 
  D

Probability of an impossible event is

• 0 A
• -1 B
• 1 C
• ∞ D

In a school there are 150 students Out of these 80 students enrolled for mathematics class.50 enrolled for English class and 60 enrolled for Physics class The student enrolled for English cannot attend any other class but the students of mathematics and Physics can take two courses at a time find the number of students who have taken both physics and mathematics.

• 40 A
• 30 B
• 50 C
• 60 D

• 1 / 2 A
• 1 / 3 B
• 1 / 4 C
• None of these D

Product of any n consecutive positive integers is divisible by

• n A
• √n B
• n! C
• None D

(n + 2) (n + 1) n= ______

• 
  A
• 
  B
• 
  C
• 
  D